Embryonic Stem Cell Trial Delayed

The New York Times, August 18, 2009

In the latest chapter of the ongoing saga over the first clinical trial ever to be conducted with human embryonic stem cells (hESCs), a new delay has presented itself.

Specifically, representatives of the Geron Corporation have announced today that U.S. federal regulators have placed a halt on the clinical trial that Geron was scheduled to conduct, before even one patient could be enrolled in the study.

Although a number of people among the non-scientific communities have expressed surprise over what they consider to be an unexpected announcement, there are many among the scientific community who find such a delay to be completely unsurprising and even predictable.

Frought with doubts and problems from the very start, the clinical trial was intended to use hESCs in the treatment of spinal cord injury. Because it would have been the first such study ever to be conducted with hESCs, the proposed clinical trial has repeatedly been the subject of widespread speculation and controversy. Now, this new ruling by the FDA, which brings all the momentum of the entire project to a grinding halt, has merely incited a new round of speculation and controversy.

The U.S. federal regulators decided to impose a halt on the clinical trial as a direct result of new data that Geron disclosed to the FDA, regarding dose escalation in preclinical animal studies. In January of this year, the FDA lifted an additional halt that it had previously imposed on Geron in May of 2008. This time, the new halt is based on safety concerns triggered by the new higher-dose data.

According to Joseph Pantginis, an analyst with the Merriman Curhan Ford Group in New York, "They are at the forefront, which a lot of times is a bit of a curse. They have to hit all the hurdles and be the first one to learn about how these cells behave."

In an official statement issued by representatives of Geron, the company "will work closely with the FDA to facilitate their review of the new data and to release the clinical hold."

Anna Krassowska, a spokesperson for Geron, stated to the press that the company had no further comment.

The news release posted on Geron's website was brief, at only two paragraphs in length, not counting the customary "forward-looking statements" and "safe harbor" disclaimers. As stated on the comapny's website, "GRNOPC1, a cell therapy for neurologically complete, subacute spinal cord injury, has been placed on clinical hold by the FDA pending the agency's review of new nonclinical animal study data submitted by the company. A clinical hold is an order that the FDA issues to a sponsor to delay a proposed trial or to suspend an ongoing trial. ... No patients have yet been treated in this study."

As the New York Times article concludes, "While thousands of patients around the world have been treated with adult stem cells and have shown mixed results, no humans have been given cells derived from embryos in an approved trial."

Indeed, it would seem as though, once again, embryonic stem cells remain confined to the experimental, laboratory stage, unable to progress to clinical trials. Meanwhile, by comparison, numerous types of adult stem cells have already advanced to Phase III clinical trials and beyond, and in fact have already been in use as viable therapies in clinics around the world for years.